Main differences between SFP and SFP28 transceivers

1. Rate

SFP: SFP modules are available in transmission rates from 1 Gbps to 10 Gbps, with 1 Gbps (SFP) and 10 Gbps (SFP+) versions commonly available.

SFP28: SFP28 modules are designed for 25 Gbps transmission rates and have higher bandwidth compared to SFP+ (10 Gbps) to accommodate high-speed networks.

2. Bandwidth

SFP: Lower bandwidth for Gigabit Ethernet (1 Gbps) to 10 Gigabit Ethernet (10 Gbps).

SFP28: Higher bandwidth, designed for high-speed applications up to 25 Gbps, better suited to meet the high bandwidth demands of modern data centres.

3. Compatibility

SFP: Supported protocols include 1G/10G Ethernet.

SFP28: Supports 25G Ethernet and is backward compatible with 10G Ethernet, so it can be used to connect to 10G-enabled devices (backward compatible).

4. Power consumption

SFP: Usually the power consumption is low, around 1W.

SFP28: Due to the higher transmission rate, the power consumption is also slightly higher, usually around 1.5W.

5. Application Scenarios

SFP: Mainly used in Gigabit and 10 Gigabit networks, suitable for small and medium-sized networks or scenarios that do not require extremely high bandwidth.

SFP28: Widely used in data centres, cloud computing and high performance computing (HPC) and other scenarios that require 25G networks, which is more suitable for future high-speed network requirements.

Summary

The difference between SFP and SFP28 modules mainly lies in the rate and application scenarios. SFP is suitable for 1G to 10G networks, while SFP28 is designed for 25G networks with higher bandwidth, suitable for modern data centre environments that require higher data transfer rates.